Air filter

ABSTRACT

An air filter including an open end, a closed end, and a filter area there between. The open end frictionally engages and seals an air port, while the closed end mates with the housing to secure the filter to the housing. The filter area is reinforced to provide a durable, reusable filter. The filter material is selected to provide depth loading and increase the particulate capacity of the filter.

PRIORITY CLAIM

This application claims priority to the U.S. patent application Ser. No.14/210,678 filed Mar. 14, 2014 and U.S. Provisional Patent ApplicationNo. 61/798,377 filed on Mar. 15, 2013, which is incorporated inentirety.

FIELD OF THE INVENTION

The field of the invention is generally related to filter devices. Morespecifically, the field of the invention is related to vehicle airfilters.

BACKGROUND

An air filter designed to remove particulate is generally a devicecomposed of fibrous materials. These fibrous materials may remove solidparticulates such as dust, pollen, mold, and bacteria from the air. Airfilters are used in applications where air quality is important, notablyin building ventilation systems and in engines.

Air filters may be used in automobiles, trucks, tractors, locomotivesand other vehicles that use internal combustion engines. Air filters maybe used with gasoline engines, diesel engines, or other engines that runon fossil fuels or other combustible substances. Air filters may be usedwith engines in which combustion is intermittent, such as four-strokeand two-stroke piston engines, as well as other types of engines thattake in air so that a combustible substance may be burned. For example,air filters may be used with some gas turbines. Filters may also be usedwith air compressors or in other devices that take in air.

Filters may be made from pleated paper, foam, cotton, spun fiberglass,or other known filter materials. Generally the air intakes of internalcombustion engines and compressors tend to use either: paper, foam, orcotton filters. Some filters use an oil bath. Air filters for internalcombustion engines prevent abrasive particulate matter from entering theengine's cylinders, where it would cause mechanical wear and oilcontamination. In many fuel injected engines, a flat panel pleated paperfilter element may be used. This filter is usually placed inside aplastic box connected to the throttle body with ductwork. Vehicles thatuse carburetors or throttle body fuel injection typically use acylindrical air filter positioned above the carburetor or throttle body.

Air filters may also be used to filter cabin air, for example, airwithin a vehicle such as a car, truck, airplane, bus, train, tractor,etc. These air filters may typically be a pleated-paper filter in whichoutside-air is passed through the filters before entering the vehicle'spassenger compartment. Some of these filters are rectangular and similarin shape to the combustion air filter.

SUMMARY OF THE INVENTION

The present invention provides an air filter. Additionally, the presentinvention may provide an air filter system and methods of using the airfilter.

Embodiments as described herein may include an air filter with a firstend, a second end, and a filter material between the first end and asecond end. The first end may include an opening for connection to apipe. An interior surface of the opening may be integrally formed withthe filter and may be configured to provide a frictional engagement withthe inserted pipe. The frictional engagement may be achieved through thecompression of the end cap around the inserted pipe. For example, aportion of the interior surface of the opening may radial expand when apipe is inserted therein. The radial expansion of a portion of theinterior surface may compress the interior surface, such that theportion of the interior surface is flattened against an exterior wall ofthe pipe. According to exemplary embodiments, the interior surface ofthe end cap may be configured to accommodate the expanded material. Forexample, the interior surface of the opening may be contoured such thatpeaks of material may be radially expanded and accommodated by troughswithin the material. In an exemplary embodiment, the peaks and troughsare created by one or more ribs of material creating one or morelongitudinally spaced rings along the interior surface projectingradially inward toward the center of the filter. An exterior surface ofthe opening may also be configured to accommodate the expansion of theinterior surface. For example, an indentation or other trough may beincluded on an exterior surface of the end cap to accommodate the radialexpansion of the interior surface.

To this end, in an exemplary embodiment, an air filter, comprising: afirst end having an opening, an interior surface defining the openingconfigured to deform and frictionally engage an air inlet; and a filtermedia coupled to and sealed to the first end.

In another exemplary embodiment, wherein the interior surface isgenerally cylindrical to create a passage to a cavity surrounded by thefilter media.

In another exemplary embodiment, wherein the interior surface iscontoured.

In another exemplary embodiment, wherein the interior surface comprisesat least 2 circumferential ribs surrounding the opening longitudinallyspaced along the opening.

In another exemplary embodiment, wherein the first end comprises agenerally planar disk with a central opening, and a rim integrallyformed with the generally planar disk extending in an outwardlongitudinal direction from the generally planar disk circumferentiallysurrounding the opening.

In another exemplary embodiment, wherein the first end comprises acircumferential indention surrounding the rim.

In another exemplary embodiment, wherein the interior surface comprisesat least one peak and one trough so that the peak deforms when contactedby the air inlet.

In another exemplary embodiment, wherein the peak and troughcircumferentially surround and define the opening.

In another exemplary embodiment, wherein the at least one peak is acircumferential ring projecting into the opening.

In another exemplary embodiment, further comprises a second end oppositethe first end, wherein the second end is closed and the filter media issealed between the first end and the second end.

In an exemplary embodiment, a method of filtering air, comprising:coupling an air filter to an conduit such that an engagement surface ofthe air filter is deformed to sealingly engage the air filter to theconduit; and passing a contaminated air stream through a filter media ofthe air filter.

Still another exemplary embodiment, an air filter, comprising: a firstend configured to frictionally engage a conduit to pass a gas stream; asecond end opposite the first end; and a filter media between the firstend and the second end.

In another exemplary embodiment, wherein the first end is a generallyplanar circular end, the second end is a generally planar circular end,and the filter material creates a cylindrical filter wall between anedge region of the first end and an edge region of the second end.

In another exemplary embodiment, wherein the first end comprises aninterior surface defining an opening through the first end; wherein theinterior surface is configured to frictionally engage an insertedconduit.

In another exemplary embodiment, wherein the interior surface comprisesat least one projection fully surrounding the opening.

In another exemplary embodiment, wherein the at least one projection isconfigured to deform to conform to an exterior surface of an insertedconduit.

Various objects, features, aspects and advantages of the presentinvention will become more apparent from the following detaileddescription of preferred embodiments of the invention, along with theaccompanying drawings in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 illustrates a perspective view from a first end of an air filteraccording to embodiments described herein.

FIG. 2 illustrates a perspective view of a second end of the air filteraccording to embodiments described herein.

FIG. 3 illustrates a side view of an air filter according to embodimentsdescribed herein.

FIG. 4 illustrates a close up of an open end of the air filter accordingto embodiments described herein.

FIG. 5 illustrates an exemplary embodiment of the air filter medium.

FIG. 6 illustrates a cross section cut away of a first end of anexemplary air filter according to embodiments described herein.

FIG. 7 illustrates the exemplary cross section cut away air filter ofFIG. 6 within an exemplary housing according to embodiments describedherein.

It will be understood that the terms “top,” “side,” and “bottom” used todescribe FIGS. 1-7 are intended to provide a frame of reference forpurposes of describing embodiments of the air filter. The actualorientation of the air filter in use and the direction of air flow mayvary.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In the following description of preferred embodiments, reference is madeto the accompanying drawings which form a part hereof, and in which itis shown by way of illustration of specific embodiments in which theinvention can be practiced. It is to be understood that otherembodiments can be used and structural changes can be made withoutdeparting from the scope of the embodiments of this invention.

Although embodiments of the invention may be described and illustratedherein in terms of a cylindrical air filter, it should be understoodthat embodiments of this invention are not limited to the exact shapeillustrated, but rather, include a wide variety of generally cylindricalshapes, generally circular, oval, round, curved, conical, or otherclosed perimeter shape, that provides a relatively large surface area ina given volume of the filter. Moreover, embodiments as described hereinare not limited for use as truck engine filters, but may haveapplicability in other filtration systems in which a large volume of airneeds to be treated.

An air filter including a closed first end and an open second end havingfilter material around an outer perimeter circumscribing an enclosedcavity is generally disclosed. An air filter in a generally hollowcylindrical form permits air flow through the filter material along thesides of the air filter and directs it through the central passage andthrough the open end. Thus, the air filter captures particulate andcontaminants on an outer surface of the filter for easy cleaning forrepetitive use. The filter material may be pleated or otherwise shapedto increase the surface area of the filter material around the outercircumference of the filter. The open end may be shaped to engage afilter housing and seal the filter to the housing and prevent air flowfrom bypassing the filter material. The closed end may be configuredsimilar to the to open end for ease of manufacturing and similarengagement to an attached housing.

According to embodiments as described herein, an exemplary air filter 2has a filter area 4, an open end 6, and a closed end 8. As shown in FIG.1, the filter area 4 is composed of a filter material 12 thatcircumferentially surrounds an open interior cavity 10 such that thefilter material 12 creates an exterior perimeter of at least a portionof the cavity. The exterior cross sectional shape may be generallycircular, oval, or otherwise shaped to improve the surface areaavailable for air flow passage for a given volume. The shape may beconsistent along a longitudinal length or may vary along the length. Forexample, the outer profile may taper from one end to the other.

The filter area 4 provides an area to pass an air stream and trapparticulates and other contaminates. The filter material may be paper,foam, cotton, spun fiberglass, or other known filter materials, woven ornon-woven material, synthetic or natural, or any combination thereof.The filter material may be pleated or otherwise shaped or contoured toincrease a surface area for passing the air stream to be cleaned. Thelength of the filter material 12 in the circumferential direction may belonger than the circular circumference of the filter generally, suchthat the surface area of the filter material is greater than the profilesurface area of the filter.

In an exemplary embodiment, the filter material 12 includes acombination of materials to create a hybrid filter medium. The hybridair filtration medium is a non-woven synthetic material designed to beused dry with no oil required. Many non-woven mediums have atwo-dimensional or “flat” surface. The hybrid filter media according toembodiments described herein comprised lofted non-woven syntheticfibers. This three dimensional platform adds a depth loading feature.Depth loading gives an air filter high airflow with low restrictionwhile providing large dust holding capacities. The hybrid air filtrationmedium permits a low restriction air filter that could be cleaned almostanywhere and in any way.

As shown in FIG. 5, the hybrid filter medium includes a thick loftednon-woven synthetic media. The material is pleated to increase thesurface area available for passing contaminated air. A first materiallayer 14 may be configured on the side directed toward the incoming airstream to be cleaned, (i.e. the dirty incoming air flow), while a secondmaterial layer 15 may be positioned behind the first material layertoward the exit side of the air flow (i.e. the cleaned outgoing airflow). A third layer 16 may be on the air exit side of the second layer15. The material of each of the layers may include a non-woven syntheticmaterial to promote depth loading of the deposited particulate matter.The first layer 14 may then be lofted to help enhance the depth loadingof the particulate material. The lofting may be achieved throughpricking, pulling, or otherwise separating fibers of the first layer.The first layer 14 may be very course to capture larger particulatematerial. As the air flow penetrates deeper into the media, the materialmay become finer and finer to capture increasingly smaller particulate.Therefore, for example, the material of the third layer 16 may comprisesfiner separation distances between fibers than that of the first layer14. The coarseness of the material may be constant for a given layer, ormay gradually increase or decrease across the one or more layers.

The disclosed exemplary commercial grade air filters built from a newhybrid filter medium incorporates some of the best characteristics ofboth cotton and synthetic non-woven technologies. They do not requireany oil treatment and use a 3-D lofted filter surface to help reduce airfilter restriction while increasing dirt capacity. Less restrictionmeans more power and better engine efficiency. As air filter restrictiongoes up, an engine needs to expend energy “pulling” air through thefilter. This is wasted energy that is no longer available for power atthe wheels. Another air flow benefit is achieve each time the air filteris washed, restriction is reduced whereas disposable air filters slowlyincrease in restriction throughout their service life.

Additional reinforcement may be included to provide additional strengthand durability for reusable applications. Therefore, the filter may becleaned and reused instead of being discarded after each application.For example, the air filter media 12 may be positioned between one ormore layers of a reinforcing layer. As shown, a wire screen 18 may beused on an outer and/or inner surface of the filter media. The wirescreen 18 may be a powder-coated aluminum screen wire that is co-pleatedalong with the filter medium to reinforce the media material. Additionalor alternate reinforcement may be provided, for example, by an exteriorand/or interior cage 20 surrounding the filter media. For example, acriss-crossed steel cage may provide additional reinforcement for thefilter media on an interior and exterior surface of the filter. Thereinforced medium surrounded by a powder-coated steel cage may withstandthe extreme temperatures and pressures that can be present in largeturbo diesel applications. The strong and robust reinforced medium 9 maypermit the air filter to be used multiple times. For example, the airfilter according to embodiments described herein may be used in place ofup to 10 or more disposable air filters.

The air filter medium may be selected or configured to providereversible air flow or uni-directional air flow through the filter. Inan exemplary embodiment, the first material layer 14 is positioned on anexterior side of another material layer 16 so that the dirty air entersfrom an exterior surface through the filter, and travels along theinterior cavity and out the open end. The material configuration may bereversed for reverse flow, or may be symmetric or mirrored to providereversible air flow through the filter.

The filter media 12 including an interior and exterior steel cage 20 isthen held between end caps 22 and 24. The end caps may be either rubberor plastic or other deformable material sufficiently strong to supportthe filter. For example, one or both of the end caps may be moldedurethane, foam urethane, or an polyurethane elastomer, and/or maycomprise a steel, or aluminum infrastructure. In the exemplaryembodiment shown, an elastomer molded polyurethane is used to provide anadditional hardness and robust exterior seat for the filter medium. Forreusable filters, the molded elastomer is preferable over foam to reducedegradation during the cleaning process.

The first end cap 22 and/or second end cap 24 may be configured to matewith a corresponding surface of an air flow housing 42 to secure thefilter relative to the housing. As the air is directed through filterarea 4, to increase air flow and improve performance, the space aroundthe filter to the housing should be maintained. The filter is thereforepositioned within the housing to maximize the airflow and the end capsare configured to retain the filter in the desired location.

In an exemplary embodiment, the open end is configured to frictionallyengage an air flow tube 26. The engagement is also configured to sealthe filter to the tube and prevent air from bypassing the filter area 4.The engagement may be ribbed, threaded, or otherwise provide africtional, sealing engagement between the tube and filter. In anexemplary embodiment, the end cap 22 radially seals the filter to a tubeinside the air filter housing 42. The filter may touch the tube andseals to the inside edge of the air filter. The end cap 22 may beconfigured such that the terminal longitudinally outwardly facingsurface 36 of the end cap 22 is separated from the housing 42. In oneembodiment, a rubber flange may be fit over the inlet tube. The filterthen press fits over the tube, holding it in place. The filter will sealto the tube against the inner lip of the filter's flange and not thebase. The frictional engagement may be created through the compressionor deformation of the material of the end cap to conform to a surface ofthe inserted pipe.

As shown in FIGS. 4 and 6, the end cap 22 has an opening to pass airfrom or to the filter interior cavity 10. The end cap 22 includes a rim28 or projection circumferentially surrounding the opening providing andextended longitudinal interior surface adjacent the opening. Thisinterior surface 30 may be configured to frictionally engage a pipe 26and seal the filter to the pipe. As shown, the interior surface 30includes longitudinally spaced ribs 32 or rings along the interiorsurface 30 projecting inward toward the interior cavity. The peak of therib 32 engages an exterior surface of the pipe while the troughs permitthe peaks to slightly or fully deform or flatten to seal the air filterto the pipe. As seen in FIG. 6, the plurality of ribs 32 may generallyform a sinusoidal interior contoured surface such that respective peakssmoothly transition into adjacent troughs and back to the next peak. Thepeaks may comprise a curved extreme interior end that is configured todeform and flatten when engaged with an inserted air conduit. The curvedextreme interior may deform into the space provided by the adjacenttrough, thus creating a generally flat interior surface corresponding tothe exterior surface of the inserted conduit. The end 34 of the cap 22may be generally flat and abut a corresponding surface of the housing 42projecting from the pipe. This end 34 surface may provide an additionalsealing engagement to the housing. The rim 28 may also provide a flangedextension to mate with the housing and provide additional support orengagement between the housing and the filter. Thus, the outward facinglongitudinal extreme end of the end cap may comprise a stepped terminalend, such that the outer portion of the end cap may be spaced from thefilter housing, while the interior portion or terminal end of the rimmay comprise one or more engaging surfaces for the filter housing.

A radially exterior portion 36 the end cap 22 may be molded to thefilter medium and securely retain the medium in place. The rim 28, ribs32, or other surface of the end cap 22 may be used as a gasket to sealthe filter to the housing and/or pipe. Therefore, additional componentsthat may wear out or require replacement may be reduced or eliminated.

The exterior terminal end surface 36 of end cap 22 may also include oneor more expansion devices, thus permitting the end cap to accommodatedeformations caused by the temperature fluctuations experienced duringuse. For example, the exterior terminal end surface 36 may include anindention or trough 37 circumferentially surrounding and adjacent therim 28. The trough may accommodate material deformations from theinserted pipe 26 as well as from the expansion and contraction of theend cap 22 during use caused by temperature variations.

In an exemplary embodiment, the closed end 8 is configured to mate withthe housing 42 and secure the filter to the housing. The end cap 24 mayinclude a radially exterior region 39 that is molded to secure andsupport the filter medium. An interior region 38 covers the end of thefilter and seals the end to force air passage through the air filterarea 4. A flange 40 may project from the end cap 24 between the interiorregion 38 and exterior region 36. The flange may be used to frictionallyengage the housing and secure the position of the filter to the housing.The flange may act as a gasket to seal the filter to the housing. Theflange may be generally curved in a radial direction, such that theflange is a generally domed circumferential ring. Adjacent the flange 40on either or both of the interior or exterior side may be an indentationor trough 41 to permit material deformation of the end cap materialduring use.

The material of the open end 6 and the closed end 8 is sufficiently hardto retain the filter media in the desired configured and support thefilter when coupled to the housing, including the pipe. The material isalso durable enough for repeated cleaning and use. However, the materialprovides some flexibility or give so that a frictional engagement may beachieved between the filter and the inserted pipe. The materialtherefore compresses when the pipe is inserted such that a sealedengagement is achieved between the pipe and filter. The open end cap,integrated into the filter, therefore creates the attachment mechanismfor the filter to the pipe, the sealing mechanism, as well as thesupport for the filter media.

In an exemplary embodiment for use in a diesel truck, the filter has agenerally cylindrical shape, is approximately 1-3 feet, and moreapproximately 2 feet tall, and has an outer diameter of around 6 to 12inches and approximately 8-10 inches, or 9 inches. The second end cap isclosed and comprises three unique regions. The first region isapproximately ¼ to ½ of an inch, and preferably ⅜ of an inch thick, andis molded directly to the media pack. This first region is disc shapedand spans the entire end of the media pack to close off the end. Thesecond region is concentric with the first region and extends from thecenter of the first region axially away from the central interior of thefilter. The third region is annular, flat, has a uniform thickness ofunder approximately ¼ inches and preferably about ⅛ of an inch, and sitson the outside surface of the first region opposite the central interiorof the filter. The second region includes a rounded annular ridge at itsouter rim that is approximately 5 to 10 inches or approximately 7 inchesin diameter from peak to peak, with the peaks extending about ¼ to %inches and preferably approximately ½ an inch further axially away fromthe thick first region. The entire outer surface of the second region,including its generally flat center, is axially further away from thecentral interior of the filter than the first region, and is outside ofthe ends of the media pack. The third region is concentric with thefirst and second regions; however, the third region is located along theouter rim of the first region radially outside of the second region. Thethird region has an inner diameter of about 5 to 10 inches andpreferably approximately 7.5 inches and an outer diameter of about 7 to15 inches, or 7 to 11 inches, or approximately 9 inches. The firstregion connects to the second region and the third region, but thesecond and third regions do not touch or directly connect to each other.None of these regions includes any projections into the central openinterior.

Embodiments as described herein are very robust, which means they may berepeatedly cleaned and reused. The filters may be cleaned with orwithout a degreasing agent, and pressure washed, compress air blown, orwater sprayed to remove the built up particulate, including dirt andgrime from the filter material. The potential reuse of the filterreduces the cost of replacing air filters. The depth-loading of thefilter material may be washable. Because of the fitted end caps, the airfilter is removable from the housing to permit replacement, servicing,and cleaning of the filter. Moreover, when restriction builds beyond adesired level, the filter may simply be washed. So instead of shortcycling expensive disposable air filters, embodiments according to thepresent description keep restriction down and horsepower up.

It will be understood that the terms “top,” “side,” and “bottom” usedherein are intended to provide a frame of reference for purposes ofdescribing embodiments of the air filter. The actual orientation of theair filter in use and the direction of air flow may vary. In additional,the recitations to a first, second, or more components is intended notto require a specific number or location of a specific component, butmerely used as a distinguishing reference from one component to another.

Although embodiments of this invention have been fully described withreference to the accompanying drawings, it is to be noted that variouschanges and modifications will become apparent to those skilled in theart. Such changes and modifications are to be understood as beingincluded within the scope of embodiments of this invention as defined bythe appended claims. The disclosed filter is exemplary only includingone or more features of the present invention. The disclosed featuresmay be repeated, duplication, removed, reconfigured, repositioned, orotherwise modified and remain within the present disclosure.

Thus, specific embodiments and applications of air filters have beendisclosed. It should be apparent, however, to those skilled in the artthat many more modifications besides those already described arepossible without departing from the inventive concepts herein. Theinventive subject matter, therefore, is not to be restricted except inthe spirit of the appended claims. Moreover, in interpreting both thespecification and the claims, all terms should be interpreted in thebroadest possible manner consistent with the context. In particular, theterms “comprises” and “comprising” should be interpreted as referring toelements, components, or steps in a non-exclusive manner, indicatingthat the referenced elements, components, or steps may be present, orutilized, or combined with other elements, components, or steps that arenot expressly referenced. Where the specification or claims refers to atleast one of something selected from the group consisting of A, B, C, .. . and N, the text should be interpreted as requiring only one elementfrom the group, not A plus N, or B plus N, etc.

1.-16. (canceled)
 17. An air filter, comprising: a first end forreceiving an airstream; a filter medium coupled with the first end; anda second end coupled with the filter medium.
 18. The air filter of claim17, wherein the first end is configured to mate with a correspondingsurface of an air flow housing to secure the air filter relative to thehousing.
 19. The air filter of claim 18, wherein the first end comprisesa disk having a central opening and a rim surrounding the opening. 20.The air filter of claim 18, wherein an interior surface defining theopening is configured to engage an air inlet so as to maintain a spacebetween the housing and the filter medium.
 21. The air filter of claim20, wherein an engagement between the interior surface and the air inletis configured to prevent air from bypassing the filter medium.
 22. Theair filter of claim 21, wherein the engagement is configured to providea sealing engagement between the air inlet and the air filter.
 23. Theair filter of claim 21, wherein a terminal longitudinally outwardlyfacing surface of the end cap is configured to separate the end cap fromthe housing.
 24. The air filter of claim 17, wherein the filter mediumincludes a combination of materials to create a hybrid filter medium.25. The air filter of claim 24, wherein the hybrid filter mediumcomprises a non-woven synthetic material configured to be used inabsence of a filter oil composition.
 26. The air filter of claim 24,wherein the hybrid filter medium is configured to be periodicallycleaned and reused.
 27. The air filter of claim 24, wherein the hybridfilter medium comprises a thick lofted non-woven synthetic medium thatprovides a depth loading feature.
 28. The air filter of claim 27,wherein the hybrid filter medium includes a first material layer, asecond material layer, and a third material layer.
 29. The air filter ofclaim 28, wherein the first material layer is directed toward theairstream to be cleaned.
 30. The air filter of claim 29, wherein thesecond material layer is disposed on an exit side of the first materiallayer to receive the airstream exiting the first material layer.
 31. Theair filter of claim 30, wherein the third material layer is disposed onan exit side of the second material layer to receive the airstreamexiting the second material layer.
 32. The air filter of claim 28,wherein any one or more of the first material layer, the second materiallayer, and the third material layer may be lofted to enhance a depthloading capability of the filter medium.
 33. The air filter of claim 28,wherein the third material layer is configured to capture smallerparticulate than the second material layer; and the second materiallayer is configured to capture smaller particulate than the firstmaterial layer.
 34. The air filter of claim 28, wherein the hybridfilter medium is configured to accommodate a reversible air flow throughthe filter medium.
 35. The air filter of claim 28, wherein a first wirescreen is coupled with an exterior surface of the filter medium while asecond screen is coupled with an interior surface of the filter medium.36. The air filter of claim 35, wherein a first steel cage is disposedoutside the exterior surface of the filter medium while a second steelcage is disposed inside the interior surface of the filter medium.